The use of different materials in chain links of an energy guide chain is known. German laid-open application (DE-OS) No. 22 21 826 describes chain elements which are suitable for manufacture by a plastic injection moulding process or a metal die casting process. In accordance with German laid-open application (DE-OS) No. 24 15 374 the outer wide sides of the projections and/or the inner wide sides of the recesses of an energy guide chain are provided with a sliding or anti-friction material. A plastic coating is referred to as advantageous in that respect. In DE 38 06 400 the side walls of a chain link are made alternately from two different thermoplastic materials which in relation to each other have lower abrasion values than pairings comprising the same respective plastic material. British patent specification No. 982 347 shows a bearing arrangement in which the surfaces which slide against each other comprise different plastic materials.
It is further known in the state of the art for an energy guide chain to be made up of multi-part chain links. DE 17 75 053 C2 for example discloses a drag chain for lines or conduits, which is formed from alternately interconnected pairs of chain plates and individual chain plates. An individual chain plate carries a ball which is so mounted in sockets in the adjacent pair of chain plates that the pair of chain plates is hingedly connected together with the individual chain plate. Arranged between the pair of chain plates and the individual chain plate at the side walls are anti-friction intermediate layers which on the one hand are intended to provide for sealing integrity of the maximum accuracy in respect of the ball bearing assembly while on the other hand they serve to hold the ball during the assembly procedure by virtue of suitable dimensioning of the opening. Also described are bushes which are carried on the longitudinal axis of the pair of chain plates and which provide a positively locking connection between the pair of chain plates and the adjacent individual chain plate.
A further publication, German patent specification No. 12 50 711, discloses a jointed-link band for energy guide chains, the bending radius of which as between the chain links is limited by interchangeable abutment portions. The bush which is illustrated therein and which surrounds a hinge pin portion affords the adjacent chain links the sliding surface on which they perform their relative movement with respect to each other. The bush is covered over by a respective lateral disc portion at the end thereof with respect to the outward sides of a chain link.
A further link chain is described in DE 23 57 908 in which disposed in mutually oppositely arranged plates of adjacent chain links are bearing shells, in which are enclosed running balls which form a rolling bearing assembly for the chain links. That rolling bearing assembly is arranged with a radius spaced from the centre point of the pivotal connection between two chain links of a link chain. The plates of two adjacent chain links are again centred by a bush, wherein two circular support discs hold together the plates of the chain links and the bush.